Mail feeding apparatus



Aug. 27, 1968 E. A. KRUPOTICH MAIL FEEDING APPARATUS 6 Sheets-Sheet 1 Filed June 6, 1966 INVENTOR.

BY Edward A. Krupoficb w @zQiD Attorneys Aug. 27, 1968 E. A. KRUPOTICH MAIL FEEDING APPARATUS 6 Sheets-Sheet 2 Filed June 6, 1966 INVENTOR.

BY Edward A Krupofich $2144 @leiw'ib Attorneys Aug. 27, 1968 E. A. KRUPOTICH MAIL FEEDING APPARATUS 6 Sheets-Sheet 3 Filed June 6, 1966 INVENTOR.

BY Edward A. Kruporich- Attorneys mfm Aug. 27, 1968 E. A. KRUPOTICH MAIL FEEDING APPARATUS 6 Sheets-Sheet 4 Filed June 6, 1966 INVENTOR.

Edward A. Krupofich BY Attorneys Aug. 27, 1968 6.Shets-Sheet 5 Filed June 6, 1966 aw wfi O h e T 0 w n N m EU 0| v r W A m w w d E w. u m n 7 g 27, 1963 E. A. KRUPOTICH 3,398,947

MAIL FEEDING APPARATUS Filed June 1966 6 SheetsSheet 6 Fig. 8

INVENTOR. Edward A. Krupofich JJZ @AQ Attorneys United States Patent ice 3,398,947 Patented Aug. 27, 1968 3,398,947 MAIL FEEDING APPARATUS Edward A. Krupotich, Palo Alto, Calif, assignor to Mail Systems Corporation, Redwood City, Calif., a corporation of California Filed June 6, 1966, Ser. No. 555,375 8 Claims. (Cl. 271-71) ABSTRACT OF THE DISCLOSURE Sheet feeding apparatus, particularly useful in feeding unsealed envelopes in a manner serving to form a stack of unsealed envelopes wherein each succeeding envelope in the stack is nested between the flapand pocket portion of the envelope next beneath. Tiltable weighing platforms arranged in a series are each quickly cleared of envelopes discharged from same in response to weighing movements. The departing envelopes being discharged from a particular weighing platform are power fed downwardly into sorting cribs whereby the leading edge of the envelope is positively driven into engagement with the upper surface of the top envelope to each stack.

This invention relates to sheet feeding apparatus which is particularly useful in feeding unsealed envelopes in a manner serving to form a stack of unsealed envelopes wherein each succeeding envelope in the stack is nested between the flap and pocket portion of the envelope next beneath. The invention is also particularly useful in conjunction with mail sorting apparatus of a kind as shown, for example, in my US. Patent No. 3,220,547.

In general, it is an object of the present invention to provide an improved sheet feeding apparatus for feeding and sorting envelopes at increased speed.

It is another object of the invention to provide sheet feeding apparatus for forming stacks of unsealed envelopes wherein each succeeding envelope in the stack is nested betwen the fiap and pocket portions of the envelope next beneath.

Another object of the invention is to provide means for quickly clearing envelopes from a tiltable weighing platform of a type, for example, wherein a series thereof serve to define the path of movement of envelope through mail sorting apparatus and upon tilting serve to discharge an envelope therefrom.

Still another object of the invention is to provide positive action power feeding of envelopes into sorting cribs whereby the leading edge of each envelope is positively driven into engagement with the upper surface of the top envelope to each stack.

These and other objects of the invention will become more readily apparent from the following detailed description of a preferred embodiment of the invention when considered in conjunction with the accompanying drawmgs.

Referring to the drawings:

FIGURE 1 is a side elevation section view of a system according to the invention;

FIGURE 2 is an enlarged and simplified side elevation view showing two weighing platforms and a portion of the belt drive arrangement;

FIGURE 3 is an enlarged and simplified side elevation view showing a portion of means for sensing jammed weighing platforms;

FIGURE 4 is a diagrammatic view showing tilting of a weighing platform;

FIGURE 5 is a plan view of FIGURE 1 taken along line 5-5 thereof; I

FIGURE 6 is a side elevation view, partially broken away, of FIGURE 5;

FIGURE 7 is an elevation section view of a portion of FIGURE 5 taken along line 7--7 thereof; and

FIGURE 8 is a diagram showing manipulation of an envelope being handled by the apparatus according to the invention.

In general, there is provided apparatus for feeding sheets such as envelopes along a path of envelope movement. The path includes a platform tiltable between envelope receiving and envelope discharging positions. Means formed of converging surfaces serve to define a guide throat in position adapted to receive the leading edge of discharged envelopes. Thus, feed rollers disposed with their treads in opposed relation defining a'nip therebetween, lie in position whereby the nip is adapted to receive the leading edge of envelopes being discharged from the platform. Prior to departure of the trailing edge of the envelope from the titlable platform, the leading edge of the envelope is received in the nip of the rollers. Further, the apparatus initiates a return of the platform to its envelope receiving position prior to the time when the trailing edge of the envelope clears the platform so that the return movement of the platform serves to lift the trailing edge of the envelope to guide the envelope to the center of the nip between the rollers. Thus, the leading edge of the envelope is guided surely into the very throat of the nip defined between the rollers so as to enhance the grip of the rollers upon the envelope.

Means are further provided which, in general, are primarily useful in nesting each succeeding envelopewith the preceding envelope discharged from the feed rollers. Accordingly, an inclined tray is disposed beneath the feed rollers and is cooperatively spaced therefrom a distance adapted to be not substantially greater than that envelope dimension defined normal to the leading edge thereof. The tray (or the upper surface of any envelopes stacked on the tray) will be skiddingly engaged by the leading edge of an envelope before the trailing edge of the same envelope is released from the feed rollers. Thus, the downward thrust applied to the envelope by the feed rollers is utilized not only to wedge the arriving envelope between the open flap portion and pocket portion of the preceding envelope, but also to drive the tray yieldingly downwardly.

The foregoing explanation provides a general description of the details of apparatus as now to be described in conjunction with portions of the construction taken from the above identified patent.

A series of tandemly arranged weighing platforms l1 serve to define a path of envelope movement for feeding envelopes and for sorting same into the several cribs 12 located beneath each platform. An intermittently driven cyclic carrier 13 formed with spaced outwardly extending projections 14 serves to advance envelopes from one platform 11 to the next.

Each platform 11 is tiltable between envelope receiving and envelope discharging positions. Each platform 11 is mounted on a scale beam 23 whereby each crib will receive those envelopes having a predetermined Weight different from that of envelopes received at the other cribs. Thus, each platform is arranged to move to a lowered position upon receipt of an envelope of a predetermined minimum weight associated with the particular platform. The predetermined minimum weight requisite becomes progressively less for the platforms at greater distances along the path measured from the starting point. Upon lowering any one or more of the platforms, the platform will be tilted to divert the envelope disposed thereon into its associated crib 12.

Each platform 11 is arranged to be rocked through a relatively large angle about an axis defined by knife edge members 17 so as to divert an envelope thereon from the path of mail movement and into the associated crib 12.

Means for rocking any of the platforms 11 which have been moved to their lowered position includes a yoke 18 disposed in fixed relation on one side of each platform 11. Yokes 18 each include a downwardly depending leg 19 adapted to rotate the platform about the axis defined by knife edge members 17. This rotation is through a relatively large angle to tilt platforms 11 for disposal of an envelope resting thereon.

A stabilizing member 21 provided with a bifurcated upper end is mounted to move in parallelism with leg 19 by means of an extended stay 22 pivotally mounted through the lower ends of leg 19 and member 21. A balance beam 23 is supported upon a fulcrum 24 carried by a channel iron side frame member 26 and held in fixed relation thereto by a set screw 27. Fulcrum member 24 is formed with a pivot pin 28 extending through a side frame member 26 and adapted to pivotally carry the bifurcated upper end portion of stabilizer member 21.. Beam 23 is provided with a V-shaped insert received in a rectangularly shaped notch at 29 whereby fulcrum 24 supports beam 23 for rocking, weighing movement about an axis defined by the insert.

At one end of beam 23, a counterweight tray 31 is mounted to carry counterweight 32 removably resting on tray 31. A first fixed stop 33 in the form of an adjustable screw serves to limit upward travel of one end of beam 23 so as to define the uppermost position of platform 11. A second fixed stop 34 serves to limit upward travel of the other end of beam 23 to define the lowermost position of the platform.

Another fixed stop 36 in the form of an adjustable screw serves to limit rotational movement of stabilizer member 21 about a pivot point 37. A spring 38, fixed at one end to a frame portion and at the other end to stabilizer member 21, serves to retain stabilizer member 21 in vertical orientation during weighing movement of leg 19.

However, as will be further described below, spring 38 permits rocking movement of stabilizer member 21 about pivot point 37 under longitudinal displacement of extended stay 22. Accordingly, spring 38 serves to provide resilient means urging stabilizing member 21 firmly against fixed stop 36 to hold stabilizer member 21 upright during vertical weighing movement of platform 11. Also, spring 38 serves to yield under substantial forces acting to move extended stay 22 in a direction generally parallel with beam 23.

Whenever leg 19 is carried to its lower position by a minimum weight on platform 11, a cyclically driven pawl 39 engages and moves extended stay 22 longitudinally of beam 23. Extended stay 22 carries a tooth 41 extending therefrom adapted to move into the path of the cyclic moving pawl 39 whenever platform 11 and leg 19 are carried downwardly from their raised position. When leg 19 is in its raised position, tooth 41 rides along the upper arcuate surface formed by the edge 42 of pawl 39. Subsequent downward movement of leg 19 during one cyclical operation is thereby precluded.

In short, the longitudinally reciprocating pawl 39 engages tooth 41 whenever the weight upon platform 11 is sufficient to move tooth 41 into the path of the leading end of pawl 39.

A pair of guide plates 43, 44 serve to define a hopper 46 disposed in position beneath each weighing platform 11 so as to receive therein envelopes which are discharged. Hopper 46 serves to direct each envelope received therein into the nip 47 defined between two pairs of feed rollers 48, 49. Thus, plates 43, 44 are spaced apart at their lower edges to form an open throat 51 through which each discharged envelope will pass. Throat 51, as thus defined, is located so as to direct the leading edge of each envelope into nip 47.

The two feed rollers 48 are mounted upon a power driven axle 52, whereas feed rollers 49 function as idler wheels. As thus arranged, each pair of feed rollers is disposed in opposed tread relation so as to define nip 47 between converging tread surfaces.

Means for driving feed rollers 48 includes the motor 50 and drive belt arranged in conventional fashion around pulleys, each of which. is fixed to the end of axle 52.

Means are provided for yieldingly urging idler rollers 49 toward the power rollers 48. A spring member 53 engages the axle 54 supporting rollers 49. Spring member 53 is pivotally supported at 56 whereby the other end of spring member 53 bears against the underside of plate 43. An adjustment screw 57 serves to adjust the spring force with which spring 53 carries axle 54 toward roller 48.

The apparatus as provided herein is arranged whereby as each envelope is discharged, the envelope pivots about its leading edge as it enters nip 47 whereby the leading edge seeks the center of nip 47. This action enhances the efficiency with which feed rollers 48, 49 engage the envelope. Thus, envelopes are cleared from platforms 11 more rapidly whereby the feeding of envelopes in the path defined by platforms 11 can be at substantially greater speed.

Rollers 48. 49 are disposed whereby nip 47 lies in a position adapted to receive the leading edge of each discharged envelope before the trailing edge of the same envelope clears the platform 11 from which it came. In the operation of the apparatus, platform 11 will commence a return movement to its horizontal orientation prior to departure of the trailing edge of the envelope from the platform. This action serves to lift the trailing edge of the envelope to pivot the envelope about its leading edge.

A particularly important use of the apparatus as described herein is in nesting a series of unsealed envelopes in a manner as required by certain postage meter devices. Accordingly, unsealed envelopes fed face up, with the sealing flap 58 in a trailing position and folded underneath, move along the path of mail movement in the direction of arrow 59. Upon arrival at a given platform 11 whereby the weight of the envelope serves to lower the platform and cause it to be tilted, the envelope will be discharged downwardly and rearwardly (according to the style of operation as shown in the apparatus in the above identified patent). At this point in the movement of the envelope, flap portion 58 will be oriented on the leading edge of the envelope as it enters nip 47.

The use of two laterally spaced pairs of feed rollers serves to feed the envelopes substantially in a straight direction of travel. As the envelope passes between feed rollers 48, 49, under the pivoting action of weighing platform 11, it will move downwardly in an upstanding plane substantially vertical and preferably slightly beyond the vertical. Thus, the axes of rotation of rollers 48, 49 serve to define a generally horizontal plane. In this downward plane of travel of the envelope through the feed rollers, the envelope can be turned over whereby the unsealed flap portion 58 will be located on the upper side of the discharged envelopes as they are stacked therebeneath. It is, therefore, preferred to cause each envelope to move through nip 47 in a plane 73 (FIG. 8) slightly beyond the vertical, i.e., whereby each envelope is flipped through an angle transcending the vertical, so that the angle of attack of envelopes with respect to a receiving tray 61 therebeneath will be somewhat acute rather than substantially perpendicular thereto. Thus axle 52 is slightly lower than axle 54 to improve this angle of attack. The term generally horizontal is therefore to be understood as including the foregoing variation.

Beneath rollers 48, 49 means have been provided for accumulating a stack of envelopes for nesting unsealed envelopes as above described. Thus, a tray 61, inclined at a substantial angle to the horizontal, is located beneath feed rollers 48, 49, and is cooperatively spaced therefrom a distance whereby tray 61 (or the upper surface of the topmost envelope stacked thereon) engages the leading edge of each discharged envelope before the trailing edge is released by feed rollers 48, 49.

In this manner feed rollers 48, 49 serve to positively thrust the leading edge of each discharged envelope against the upper surface of the accumulation of envelopes upon tray 61. In this way, the leading edge of the envelope skids along the uppermost envelope and forces its way between the pocket portion and the unsealed flap portion 58 of the underlying envelope so that the arriving envelope is properly nested.

In addition to the weight of the stack of envelopes, the foregoing action also tends to urge tray 61 downwardly but under positive forces derived from the feed rollers so as to overcome sticking in the initiation of downward tray movement, sometimes referred to as stiction.

Thus, tray 61 is supported upon extension 62 which is telescopically slidable vertically in a guide-way 63. A spring 64 serves to yieldingly urge tray 61 upwardly. The upper end of spring 64 engages a pin 66 fixed to the frame of the apparatus. The lower end of spring 64 engages one end of chain 67, which, in turn, is secured by a pin fixed to stanchion 62. The links of chain 67 may be readily used to introduce adjustments to spring tension.

Means are provided for adjusting the angle at which tray 61 is disposed. The upper end of stanchion 62 carries an angularly disposed support bar 68. A leaf spring member 69 is attached at one end to tray 61 and at its other end to support bar 68. An adjusting screw 71 is threadedly engaged through support bar 68 whereby the upper end of screw 71 contacts tray 61 and thereby serves to either enlarge or contract the angle defined by leaf spring member 69. Thus, screw 71, when screwed upwardly, moves tray 61 to become more horizontally oriented.

It has been observed that by disposing plate 43 at a substantial angle to the horizontal and taking the foregoing steps to ensure each envelope is pivoted upwardly so as to enter nip 47 in an upstanding plane approaching the vertical, the reversely inclined plane defined by tray 61 receives the discharged envelopes in an orientation whereby the leading edge of each arriving envelope will readily serve to scrape open and enter the gap between the unsealed flap portion 58 and the backside of the pocket of the topmost envelope carried by tray 61.

Each of the power driven feed rollers 48 is disposed in a position farthest from the leading edge of envelopes being discharged into nip 47. Roller 48 is also relatively large and is disposed whereby the leading edge of each envelope arriving via throat 51 attacks the tread portion of roller 48 in a plane substantially normal to a plane tangent to roller 48. Roller 48 is further characterized by a corrugated peripheral surface 72 wherein the corrugations extend substantially parallel to axle 52. The corrugations of surface 72 serve to positively engage the leading edge of each envelope and impart a downward motion thereto which further tends to pivot the trailing edge of the envelope into an upstanding plane through nip 47.

In the foregoing manner, and in addition to the boosting action imparted to the trailing edge of each envelope by the return movement of weighing platforms 11, the corrugated surface 72 more or less grabs the leading edge of each envelope to further aid in snapping the envelope into an upstanding plane for delivery substantially directly downwardly through nip 47. Further, as each envelope is discharged through feed rollers 48, 49 its leading edge will be forcefully urged against the upper surface of the topmost envelope carried by tray 61 whereby the unsealed fiap 58 of the topmost envelope will be forced open. At the same time, tray 61 receives a downward thrust tending to impart downward movement to the tray.

By thus disposing the plane defined by axles 52, 54 at a distance beneath platforms 11 not substantially greater than that envelope dimension defined in a direction normal to the leading edge thereof, each envelope will be engaged in nip 47 prior to the time that the trailing edge of the envelope clears platform 11.

The normal cycle of operation for the apparatus as shown in the above identified patent (and shown herein in part only) when the motor 16 thereof is driven at a speed on the order of 60 rpm. (and reduced by the gearing to feed envelopes of the usual ofiicial business type at a rate on the order of fifty per minute), will readily serve to initiate a return movement of platform 11 to its envelope receiving position prior to departure of the trailing edge of each envelope therefrom. Certain components of the apparatus disclosed in the above identified patent are also shown herein and identified by those reference numerals appearing in parentheses.

From the foregoing description, it should be readily evident that there has been provided a sheet feeding apparatus particularly useful in feeding envelopes at a high rate.

The high rate of feeding is aided by the cooperative relation of feed rollers disposed beneath a tiltable platform which discharges the envelopes as they are fed along a path of envelope movement. Thus, the weighing platform lifts the trailing edge of each envelope so as to pivot the envelope about its leading edge which is then engaged in the nip of the feed rollers. In addition, the feed roller furthest from the leading edge of the envelopes being discharged, more or less grips the leading edge of the envelope and causes the envelope to be further pivoted upwardly into a substantially vertical plane due to positive engagement of the leading edge of each envelope with the corrugations of the feed roller.

Finally, and as is particularly useful in nesting a number of unsealed envelopes, the feed rollers are cooperatively disposed with respect to the top of a tray for receiving and stacking envelopes whereby a positive thrust is applied by the feed rollers to each envelope as the leading edge of the envelope engages the upper surface of inclined envelopes stacked on the tray.

I claim:

1. In apparatus for feeding envelopes, means defining a path of envelope movement including a platform tiltable between envelope receiving and envelope discharging positions, means formed of converging surfaces serving to define a guide throat in position adapted to receive generally therein the leading edge of an envelope being discharged from said platform prior to departure of the trailing edge of the envelope from the platform, and means serving to initiate a return of said platform to its envelope receiving position priorv to said departure to lift said trailing edge for guiding the envelope in said throat.

2. In apparatus for feeding envelopes, means defining a path of envelope movement including a platform tiltable between envelope receiving and envelope discharging positions, at least a pair of feed rollers disposed in opposed tread relation to define a nip therebetween, said nip lying in position adapted to receive therein the leading edge of an envelope being discharged from said platform prior to departure of the trailing edge of the envelope from the platform, and means serving to initiate a return of said platform to its envelope receiving position prior to said departure to lift said trailing edge for guiding the envelope in said nip.

3. In apparatus for feeding envelopes and for inverting same, apparatus comprising means defining a path of envelope movement including a platform tiltable between envelope receiving and envelope discharging positions, at least a pair of feed rollers disposed in opposed tread relation to define a nip therebetween, the axes of rotation of said rollers lying in a generally horizontal plane, said nip lying in position adapted to receive therein the leading edge of envelopes being discharged from said platform prior to departure of the trailing edge of the envelope from the platform, and means serving to initiate a return of said platform toward its envelope receiving position prior to said departure to lift said trailing edge and pivot the envelope about the leading edge thereof then in said mp.

4. Apparatus according to claim 3 wherein the axis of rotation of that roller remote from the leading edge of the envelope being discharged lies slightly below the axis of the roller nearer said leading edge.

5. Apparatus according to claim 3 including a corrugated peripheral surface on that roller farthest from the leading edge of the envelope being discharged into said nip, the corrugations of said surface serving to be adapted to positively engage the leading edge of each envelope and impart a downward motion thereto to tend to pivot the trailing edge of the envelopes into an upstanding plane through said nip.

6. Apparatus according to claim 3 further including an inclined tray beneath said feed rollers and cooperatively spaced therefrom a distance adapted to be not substantially greater than that envelope dimension defined normal to said leading edge, said tray thereby engaging the leading edge of any envelope before release of its trailing edge by said feed rollers.

7. Apparatus according to claim 3 further including a tray for receiving and stacking envelopes beneath said feed rollers, said tray being inclined at a substantial angle opposite to that of said platform when tilted to its said discharge position, said tray being yieldingly movable between raised and lowered positions, said raised positions serving to space said tray from said rollers a distance serving to cause the leading edge of succeeding envelopes to urge the tray downwardly under forces derived from said rollers.

8. In apparatus for feeding sheet articles of a type such as envelopes, apparatus'comprising means defining a path of envelope movement, a pair of feed rollers in said path disposed in opposed tread relation to define a nip therebetween adapted to feed envelopes therethrough, a tray for receiving and stacking envelopes beneath said rollers, said tray being inclined at a substantial angle to the horizontal to maintain the top of a stack of envelopes thereon spaced a distance adapted to provide engagement between the top of the stack and the leading edge of succeeding envelopes prior to their release from said feed rollers, the orientation of said inclined tray and spacing of the stack from the feed rollers serving to cause the feed rollers to urge envelopes into the stack and drive the leading edge of the arriving envelope into the open angle formed by the overfolded flap of a preceding envelope.

References Cited UNITED STATES PATENTS 1,623,976 4/1927 Post 271-2 3,087,725 4/1963 Duncan 271-71 3,092,380 6/1963 Anderson et a1. 271-7l 3,220,547 11/ 1965 Krupotich 209-74 ANDRES H. NIELSEN, Primary Examiner. 

